onsemi BC184C

Overview

BC184C from Fairchild Semiconductor is a silicon NPN small-signal transistor designed for general-purpose amplification and switching in low-power analog and digital circuits. It features V_CEO = 30 V (min), h_FE = 130–800 (depending on I_C), f_T = 150 MHz, and is rated for 350 mW at T_A = 25°C. It is commonly used in audio preamplifiers, signal conditioning stages, and discrete logic interface circuits.

For engineers reviewing the BC184C datasheet, pinout, applications, or equivalent options, key selection criteria include DC current gain range at multiple collector currents, saturation voltage under defined drive conditions, noise figure at audio frequencies, output capacitance at 10 V, and thermal limits for through-hole TO-92 mounting in space-constrained PCB layouts.

Technical Context

The BC184C operates as a standard bipolar junction transistor with fixed NPN polarity and base-controlled current amplification. Its h_FE varies significantly with collector current - from ≥100 at 10 µA to ≥130 at 100 mA - indicating optimized linearity across mid-range bias points. The device exhibits low V_CE(sat) (0.25 V at I_C = 100 mA, I_B = 5 mA) and moderate V_BE(on) (0.55–0.7 V), supporting reliable turn-on in resistor-biased switch configurations.

With f_T = 150 MHz and C_OB = 5 pF at V_CE = 10 V, the BC184C supports RF amplification up to ~50 MHz in tuned circuits. Its noise figure is specified at 4 dB for both 200 µA and 200 mA operating points, confirming suitability for low-noise preamp stages where emitter degeneration or feedback is applied.

Key Specifications

Pinout & Package

BC184C is housed in a standard through-hole TO-92 package with 3 leads: Collector (lead 1), Base (lead 2), Emitter (lead 3), as marked on the device body and confirmed in Fairchild's Rev. A1 datasheet.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN small-signal transistor applications.

Compared with BC547C and 2N3904, the BC184C offers a uniquely balanced combination of mid-to-high h_FE, verified 4 dB audio noise performance, and stable f_T - making it especially valuable in legacy audio equipment repair, educational labs, and designs where predictable gain spread across bias points is essential.

Availability

BC184C is available at Aetrix Electronics and suitable for audio preamplifier design, discrete logic interfacing, and low-power relay driving requiring stable component supply and long-lifecycle support for industrial and educational applications.

Supply support for BC184C includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Fairchild Semiconductor was a U.S.-based semiconductor company specializing in power management, analog, and discrete components before its acquisition by ON Semiconductor in 2016.

The BC184C belongs to Fairchild's legacy silicon NPN transistor product line, engineered for general-purpose amplification and switching in consumer, industrial, and educational electronics where reliability, consistency, and proven performance at moderate frequencies are required.

FAQ

What is the maximum collector current rating for BC184C?

The BC184C has a maximum continuous DC collector current (I_C) rating of 500 mA, as specified in the Absolute Maximum Ratings table. However, practical operation is constrained by power dissipation: at ambient temperature (T_A = 25°C), the 350 mW power limit restricts safe I_C to approximately 115 mA when V_CE = 3 V. Derating is required above 25°C ambient per the thermal resistance curve in the BC184C datasheet.

Is BC184C pin-compatible with BC547 or 2N3904?

Yes, the BC184C uses the standard TO-92 package with lead configuration 1–2–3 = Collector–Base–Emitter, matching BC547 and 2N3904. Mechanical and electrical pinout compatibility is confirmed in Fairchild's Rev. A1 datasheet and cross-reference documentation. No PCB layout changes are needed for direct substitution in through-hole designs, though h_FE and noise characteristics differ.

What is the typical noise figure of BC184C and under what conditions is it measured?

The BC184C has a noise figure of 4 dB, measured under two conditions: first at I_C = 200 µA with R_G = 2 kΩ across 30 Hz–15 kHz, and second at I_C = 200 mA under identical frequency and source resistance conditions. This dual-point specification confirms low-noise performance across both small-signal and medium-current operating regions, supporting its use in wide-dynamic-range audio stages.

Can BC184C be used in RF amplifier applications?

Yes, the BC184C is suitable for RF amplifier applications up to approximately 50 MHz. Its f_T of 150 MHz and output capacitance (C_OB) of 5 pF at V_CE = 10 V provide sufficient gain-bandwidth product and low parasitic loading for VHF-stage amplification, oscillator buffering, and narrowband tuned amplifiers - provided proper impedance matching and stability compensation are implemented.

What is the minimum h_FE guaranteed for BC184C at I_C = 100 mA?

The BC184C guarantees a minimum h_FE of 130 at V_CE = 5 V and I_C = 100 mA, as stated in the Electrical Characteristics table. This value is distinct from the higher h_FE bins observed at lower currents (e.g., ≥250 at I_C = 2 mA), and reflects the device's performance under moderate-power switching or linear amplification conditions where thermal effects begin to influence gain.